COLUMBIA -- South Carolina football coach Will Muschamp has stated with regularity his team is heavy on unknowns. And even some of his most established players could stand to have more consistency going into 2017. Here are the USC’s four position groups with the most to prove.

1. Defensive line

Once flush with future NFL players and blue-chippers around them, this group had a difficult run in 2016. Not only did the Gamecocks have a substandard pass rush, but they often were pushed off the line in the run game. The group returns a couple big guys who showed flashes (Ulric Jones, Taylor Stallworth) and a couple reserve rotation ends likely stepping into starting roles (Dante Sawyer, D.J. Wonnum). USC adds JUCO four-star Javon Kinlaw, early enrollee tackle M.J. Webb and has second-year players Kobe Smith and Aaron Thompson ready to join end/tackle Keir Thomas in the rotation. The question remains, can that group succeed?

2. Offensive line

The Gamecocks built solid run-blocking lines from 2010-2014, not often dominant, but usually good. Then the bottom fell out in 2015-16 when everything became an issue. This group avoids the top spot only because of the experience returning, 98 starts, eighth nationally. That includes three players with multiple years starting and seven who’ve started at least a game. Zack Bailey’s move from guard to tackle bears watching, and the pass protection could be helped by Jake Bentley having a year in the system.

3. Secondary

USC returns five “starters” and one rotation player from a group that was rag-tag in 2016 and often stretched to the limit. There’s a small army of new defensive backs joining (six, including a pair of junior college players), and just about everyone could stand to be pushed. Corner Jamarcus King could be a star if he takes a step forward, but he’ll need more strength and consistency. USC wasn’t bad at preventing big plays, but has to get better at putting opponents behind the chains and getting them off the field.

4. Linebacker

This is more about personnel than past performance. The Gamecocks return only three linebackers. Bryson Allen-Williams was an anchor. Skai Moore missed the year with injury. T.J. Brunson played, maybe, 50 snaps. They’ll need more than those three just to field a rotation. The three incoming freshmen are intriguing, and Eldridge Thompson could have a bright future as a space backer and in coverage, but he might need more development.